Process and catalyst for production of olefin polymers



United States Patent PROCESS AND CATALYST FOR PRODUCTION OF OLEFINPOLYMERS Gene Nowlin and Harold D. Lyons, Bartlesville, 0kla.,

assignors to Phillips Petroleum Company, a corporation of Delaware NoDrawing. Application May 23, 1955 Serial No. 510,550

17 Claims. (Cl. 260--94.9)

This invention relates to the polymerization of olefins. In one aspect,this invention relates to an improved method for polymerizing olefins inthe presence of a novel catalyst system.

Reactions for polymerizing olefins are well known in the art and aregenerally carried out in the presence of catalysts. One class ofcatalysts which has been used in the polymerization of monoolefins,particularly ethylene, is organometal compounds, for exampletriethylaluminum, and the polymers which have been obtained inaccordance with this method are generally liquid or low molecular weightsolid polymers. Frequently, the polymers obtained are dimers or trimersof the olefin charged. The most valuable polymers, however, are highermolecular weight polymers which have desirable properties of heatstability and can be molded into vessels, pipes and tubing. Such usescannot be made of the lower molecular weight polymers, for example, apolymer having a molecular weight of about 2000, since a polymer of thismolecular weight is a wax-like material.

An object of this invention, therefore, is to provide an improvedprocess for the production of olefin polymers.

A further object is to provide a novel catalyst for use in theproduction of olefin polymers.

A still further object is to produce high molecular weight solidpolymers of olefins, such as ethylene.

Other and further objects and advantages of this invention will becomeapparent to those skilled in the art upon consideration of theaccompanying disclosure.

It has now been discovered that an unexpected improvement is obtainedwhen an olefin such as ethylene is polymerized in the presence of acatalyst composition comprising a mixture of a complex metal halidehaving the formula M MX wherein M is an alkali metal or ammoniumradical, M is a metal of Group IV-A (Mendeleffs Periodic System),including titanium, zirconium, hafnium and thorium, and X is a halogen,preferably fluorine or chlorine, and at least one component selectedfrom the following (a) a hydride or organo compound of one of the metalsaluminum,

gallium, indium, thallium, sodium, potassium, lithium, rubidium, cesium,beryllium, magnesium, zinc, cadmium and mercury; (b) an organometalhalide corresponding to the formula R MX wherein R is a saturatedacrylic hydrocarbon radical, a saturated cyclic hydrocarbon radical, anaromatic hydrocarbon radical, or combination of these radicals, whereinM is a metal selected from the group consisting of aluminum, gallium,indium, thallium, and beryllium and wherein X is a halogen, and whereinn and y are integers, the sum of n and y being equal to the valence ofthe metal; (c) a mixture of an organic halide and at least one metalselected from the group consisting of sodium, potassium, lithium,rubidium, cesium, beryllium, magnesium, zinc, cadmium, mercury,aluminum, gallium, indium and thallium; and (d) a metal selected fromthe group con- ,sisting of sodium, potassium, lithium, rubidium, cesium,

beryllium, magnesium, zinc, cadmium, mercury, aluminum, gallium, indiumand thallium. As indicated, the catalyst composition of this inventioncomprises a complex metal halide of formula MMX, where the symbols ofthe formula are as indicated above, together with mixtures of components(a), (b), (c) and (d) as well as mixtures of the aforementioned complexmetal halide and any one, two, three or four of components (a), (b), (c)or (d). The improvement obtained when polymerizing an olefin in thepresence of our novel catalyst is, firstly, that polymers of much highermolecular weight can be obtained than is true when certain of the priorart catalysts have been employed, and secondly, the polymerizationreaction, particularly for ethylene, can be initiated and carried out atconsiderably lower temperatures and pressures than are necessary whenemploying the catalysts and the processes of the prior art.

The complex metal halide component of our catalyst system comprises atleast one of the compounds corresponding to the formula M M'X wherein Mis one of the group consisting of sodium, potassium, lithium, rubidium,cesium and ammonium radical, M is one of the group consisting oftitanium, zirconium, hafnium, and thorium, and X is one of the groupconsisting of bromine, chlorine, fluorine and iodine. Mixtures of two ormore of these complex halides can be employed in the practice of thisinvention. In general, these compounds are relatively high meltingsolids, and it is believed that they are complex metal halide salts. Anyof the known or available complex salts, including potassiumfluotitanate (K TiF potassium fluozirconate (K ZrF lithium fluotitanate(Li TiF potassium chlorozirconate (K ZrCl cesium fluozirconate (Cs ZrFammonium chlorotitanate ((NH TiCl potassium fluothoriate (K ThF andpotassium fluohafniate (K HfF can be employed in our process. Thecomplex metal halides which are preferably used in the catalystcomposition of this invention are potassium fluotitanate and potassiumfluozirconate.

In admixture with one or more of the complex metal halides describedabove, our novel catalyst comprises a hydride or organo compound of themetals aluminum, gallium, indium, thallium, sodium, potassium, lithium,rubidium, cesium, beryllium, magnesium, zinc, cadmium, and mercury. Thegeneral formula for the latter compound is M'R',,, wherein M is one ofthe foregoing metals, and R is a hydrogen, a monovalent saturated acylichydrocarbon radical, a monovalent saturated cyclic hydrocarbon radical,a monovalent aromatic hydrocarbon radical or any combination thereof,and wherein n is the valence of the metal, i.e., l, 2 or 3. Examples ofthese compounds corresponding to the formula MR' which can be used areAl(C H 3)a 2 5)2 z 3, l 3)2, AlHa,

C H Na, CgHqK, C H Li and the like. These MR compounds can also be usedin the form of their known and stable organic complexes, such ascomplexes with ethers, thioethers, amines, alkali metal hy-drides,alkali metal alkyls or alkali metal aryls. Examples of such complexcompounds which can be used in admixture with a complex metal halide asthe catalyst are LiAlH NaA1(CH NaBe(C H NaBe(C H and the like.

Alternatively, or in addition to MR compounds set forth above, ourcatalyst comprises a mixture of one or more of the complex meta] halidesand at least one organometal halide corresponding to the formula R MXwherein R is a saturated acyclic hydrocarbon radical, a saturated cyclichydrocarbon radical, an aromatic hydrocarbon radical, or mixtures ofthese radicals, wherein M is a metal selected from the group consistingof aluminum, gallium, indium, thallium and beryllium, and wherein X is ahalogen. The n and y are integers and the sum of n and y is equal to thevalence of the metal M. X can be any of the halogens, includingchlorine, bromine, iodine and fluorine. The saturated acyclichydrocarbon radicals, saturated cyclic hydrocarbon radicals, andaromatic hydrocarbon radicals which can be substituted for R in theformula include hydrocarbon radicals having up to about 20 carbon atomseach. Radicals having 10 carbon atoms or less are preferred since theresulting catalyst composition has a greater activity for initiating thepolymerization of olefins. Mixtures of one or more of these organometalhalide components, such as a mixture of ethylaluminum dichloride anddiethylaluminum chloride, can be'used in our catalyst composition.Specific examples of other organometal halides which are useful in thecatalyst composition of this invention are the following: CH AlCl (CHAlCl, C H AlCl (C H A1Cl, (C H AlBr, CaHwAlIz, (C H GaF, (C H GaCl(cyclohexane derivative), (C H )GaBr (benzene derivative),

(C I-I GaF, (C H InCl (benzene derivative),

C H InF (C l-l QInBr (cyclohexane derivative), C H BeI,

CH BeBr and the like.

Alternatively, or in addition to the M'R compounds and/or R MX compoundsset forth above, our catalyst comprises a mixture of one or more of thecomplex metal halides and a mixture of an organic halide and a free orelemental metal. These organic halides include chloro-, bromo, iodoandfluoro-substituted organic halides, and can be mono-, di-, triortetra-substituted organic halides. Within the broad class of organichalides which is a component of our novel catalyst composition, theclass of halides defined as monohalogen-substituted hydrocarbons havinga maximum carbon chain length of not greater than 8 carbon atoms arepreferred since they are more easily handled in a commercial operationand are active to initiate the polymerization of olefins in the catalystcomposition of this invention. Still more desirably, the organic halidewhich is used in the catalyst is a lower alkyl monohalide having amaximum carbon chain length of not greater than 8 carbon atoms. Examplesof these organic halides which can be used in the catalyst are ethylbromide, propyl chloride, butyl iodide and pentyl fluoride. Otherexamples are 1,2-dibromoethane, 1,3-dibromopropane,1,2,3-tribromopropane, 1,2,3-trichloropropane, 1,1- difluoroethane, and1,4-diiodobutane. Other acyclic and cyclic halides as well as aromatichalides can be employed also. Examples of these are1,3-dichlorocyclohexane,

. benzyl chloride, 1,4-dichlorobenzene, l-bromodecane, 1-

. chlorododecane, 2-chlorooctane, 2-chloro-4-methylootane, cyclopentylchloride, l-chloro-3-phenylpropane, l-bromo- S-phenylhexane, cyclohexylchloride and phenyl chloride. Also alkenyl halides, such as allylbromide, and alkynyl halides, such as propargyl chloride, can be used.The metals which are employed in admixture with an organic halideinclude one or more of sodium, potassium, lithiurn, rubidium, cesium,beryllium, magnesium, Zinc, cadmium, mercury, aluminum, gallium, indium,and thallium. The

metals are usually used in the form of shavings, turnings and/or R MXcompounds and/or the mixture of an organic halide and a free orelemental metal, as set forth above, our catalyst comprises a mixture ofone or more of the complex metal halides and at least one metal selectedfrom the group consisting of sodium, potassium, l thium, rubidium,cesium, beryllium, magnesium, zinc,

'4 cadmium, mercury, aluminum, gallium, indium and thallium. Thesemetals are usually employed in the form of shavings, turnings or finelydivided powder and various mixtures or combinations of at least one ofthe complex metal halides and these metals can be employed as thecatalyst in accordance with this invention.

As has been indicated, all possible combinations of a hydride or organocompounds corresponding to the formula M'R and/ or an organometal halidecorresponding to the formula R MX and/ or a mixture of an organic halideand a free or elemental metal as set forth above and/or at least onemetal selected from the group set forth above together with one or moreof the complex metal halides are used in the catalyst composition ofthis invention. The catalyst compositions falling within the scope ofthis disclosure which are preferred because their use to catalyze thepolymerization of olefins provides relatively high molecular weightpolymers and/or permits the use of relatively low reaction temperaturesand pressures are the following: A mixture of potassium fluo titanatewith an approximately equimolar mixture of ethylaluminum dichloride anddiethylaluminum chloride; a mixture of potassium fluotitanate andtriethylaluminum; a mixture of potassium fluotitanate and lithiumaluminum hydride; a mixture of potassium fluotitanate, ethyl bromide andfree or elemental magnesium; and a mixture of potassium fluorzirconatewith an approximately equimolar mixture of ethylaluminum dichloride anddiethylaluminum chloride.

The amount of the catalyst composition of this inven tion which is usedin the polymerization of olefins can vary over a wide range. Relativelysmall amounts of the catalyst provide the desired activating effect whenthe polymerization reaction is carried out as a batch process withcontinuous addition of the olefin as the polymerization reaction occurs.When a continuous flow system is employed, the concentration of thetotal catalyst composi tion is usually in the range from 0.01 weightpercent to 1.0 weight percent, or higher.

The ratio of the amounts of organometal compound to complex metal halidewill usually be in the range of 0.05 to 50, preferably 0.1 to 5, mols oforganometal compound per mol of complex metal halide. The ratio of alkylmetal halide to complex metal halide will be in the range of 0.05 to 50,preferably 0.1 to 5, moles of alkyl metal halide per mol of complexmetal halide. The ratio of the amounts of organic halide, metal andcomplex metal halide will be in the range of 0.02 to 50 mols of theorganic halide per mol of the complex metal halide and from 0.02 to 50mols of the metal per mol of the com-' plex metal halide. A preferredratio is from 0.1 to 5 mols of alkyl halide per mol of complex metalhalide and from 0.1 to 5 mols of metal per mol of the complex metalhalide. When a metal of the class defined above is employed with acomplex metal halide the ratio of the components will vary from 0.02 to50 mols of the metal, preferably from 0.1 to 5 mols, of the metal permol of the complex metal halide.

The materials which are polymerized in accordance with this inventionare polymerizable hydrocarbons, broadly. Preferably, the polymerizablehydrocarbons are olefins containing a CH =C radical. The preferred classof polymerizable hydrocarbon-s used is aliphatic l-olefins having up toand including 8 carbon atoms per molecule. Specifically, the normall-olefin, ethylene, has been found to polymerize to a polymer thereofupon being contacted with the catalyst composition of this'invention atlower temperatures and pressures than have been used in the processes ofthe prior art mentioned above. Examples of other polymerizablehydrocarbons which can be used in the process of this invention arepropylene, l-butene, l-hexene and l-octene. Branched chain olefins canalso be used, such as isobutylene. Also, 1,1- dialkyl-substituted and1,2-dialkyl-substituted ethylenes can be used, such as butene-Z,pentene-Z, hexene-Z, hepttene-S, Z-methyl-butene-I, .Z-methyl-hexene-l,2-ethylheptene-l, and the like. Examples of the diand polyolefins inwhich the double bonds are in no-conjugated positions and which can beused in accordance with this invention are 1,5-hexadiene, 1,4-pentadieneand 1,4,7- octatriene. Cyclic olefins can also be used, such ascyclohexene. Mixtures of the foregoing polymerizable hydrocarbons can bepolymerized to a solid polymer in the presence of our novel catalyst as,for example, by copolymerizing ethylene and propylene, ethylene and 1-butene, propylene and l-butene, or propylene and a pentene. Also, arylolefins, e.g., styrene and alkyl-substituted styrenes can be polymerizedto a solid polymer in the process of this invention.

One of the important advantages obtained in the polymerization ofolefins in the presence of our novel catalyst is that lower temperaturesand pressures can be used than in certain of the prior art processes.The temperature can be varied over a rather broad range, however, suchas from zero to 500 F. The preferred temperature range is from 100 to350 F. Although pressures ranging from atmospheric up to 30,000 p.s.i.g.or higher can be employed, a pressure in the range of 100 to 1000 psigis usually preferred.

In this connection, it is noted that it is preferred to carry out thereaction in the presence of an inert, organic hydrocarbon diluent with apressure suflicient to maintain the diluent in the liquid phase, givingrise to a so-called mixed-phase system. However, the polymerizationprocess of this invention proceeds in the gaseous phase without adiluent. The preferred pressure range set forth above has been found toproduce solid polymers of olefins in excellent yields.

Suitable diluents for use in the polymerization process are paraffins,halogenated paraffins, cycloparaffins and/or aromatic hydrocarbons whichare relatively inert, non-deleterious and liquid under the conditions ofthe process. The lower molecular weight alkanes, such as propane,butane, and pentane can be used as well as the higher molecular weightparafiins and cycloparafi'ins, such as isooctane, cyclohexane andmethylcyclohexane. Halogented aromatics, such as chlorobenzene, andaromatic diluents can also used, such as benzene, toluene, and the like,particularly when operating at higher temperatures. Mixtures of any twoor more of these diluents can also be used.

The process of this invention can be carried out as a batch process bypressuring the olefin into a reactor containing the catalyst anddiluent, if the latter is used. Also, the process can be carried outcontinuously by maintaining the above-described concentrations ofreactants in the reactor for a suitable residence time. The residencetime used in a continuous process can vary widely, since it depends to agreat extent upon the temperature at which the process is carried out.The residence time also varies with the specific olefin that ispolymerized. However, the residence time for the polymerization ofaliphatic monoolefins, within the preferred temperature range of 100 to350 F., falls within the range of one second to an hour or more. In thebatch process, the time for the reaction can vary widely also, such asup to 24 hours or more.

Various materials are known to be poisons for the catalyst compositionsof this invention. These materials include carbon dioxide, oxygen andwater. Therefore, it is usually desirable to free the polymerizablehydrocarbon from these materials, as well as from other materials whichtend to inactivate the catalyst before contacting the hydrocarbon withthe catalyst. Any of the known means for removing such contaminants canbe employed. When a diluent is used in the process, this material shouldbe freed of contaminants, such as water, oxygen, and the like. It isdesirable also that air and moisture be removed from the reaction vesselbefore the reaction is carried out.

.,a batch process is used, the reactor is cooled to about roomtemperature, any excess .olefin is vented, and the contents of thereactor, including the solid polymer swollen with diluent, is removedfrom the reactor. The total reactor efliuent is then treated toinactivate the catalyst, as by washing with an alcohol. Thealcohol-washing step is preferably carried out in a comminution zone,such as a Waring Blender, so that afinely-divided polymer is therebyprovided. The polymer is then separated from the alcohol and diluent bydecantation or filtration after which the polymer is dried. When theprocess of the invention is carried out continuously, the total eflluentfrom the reactor, including polymer, diluent and catalyst system ispumped from the reactor as a slurry to a catalyst-inactivating zonewhere the reactor efl luent is cooled and contacted with a suitablecatalystsinactivating material, such as an alcohol. As in the batchprocess, it is desirable that the alcohol-treatment step be carried outin a comminution zone so that a finely divided polymer is therebyproduced. The diluent and alcohol are then separated from the polymer,for example by filtration and the polymer is then dried. The: diluentand alco-hol can be separated, for example by fractional distillation,and reused in the process.

EXAMPLE A catalyst composition consisting of a mixture of 2 grams ofpotassium fluotitanate (K TiF and 2.8 cubic centimeters of a mixture ofdiethyl aluminum chloride and ethyl aluminum dichloride was prepared.

The mixture of diethylaluminum chloride and ethylaluminum dichloride wasprepared by placing 150 grams of aluminum shavings in a flask fittedwith a reflux condenser and heated to about 70 C. A trace of iodine wasadded to the flask to act as a catalyst and ethyl chloride was chargedto the flask in liquid phase. The temperature of the reaction mixturewas maintained in the range of to C. during the addition of ethylchloride and the reaction mixture was maintained under a nitrogenatmosphere. When substantially all of the aluminum shavings had reactedwith the ethyl chloride, the liquid product was removed from the flaskand fractionally distilled at 4.5 millimeters mercury pressure in apacked distillation column. 2.8 cubic centimeters of the distillate,boiling at 72 to 74 C. at 4.5 millimeters mercury pressure, was used inthe catalyst composition of this invention, as set forth above. Thisfraction boiling at 72 to 74 C. was analyzed and was found to contain47.4 weight percent chlorine. The theoretical chlorine content for anequimolar mixture of diethylalurn'inurn chloride and ethylaluminumdichloride is 43 weight percent.

The potassium fluotitanate, which was in the form of light cream coloredgranular powder, was obtained from the Harshaw, Chemical Company,Houston, Texas, and had the following properties:

tpp oximately Apparent Density 10 lbs. per

gallon Assay: Percent KgTlFs 99.

.for liquids. extrusion.

with 370 cubic centimeters of cyclohexane (dried over sodium) prior tothe addition of the catalyst components. The reactor was flushed withnitrogen prior to and during the charging procedure to prevent contactof the catalyst with air or moisture. The ethylene feed was passedthrough a purification system to remove oxygen, carbon dioxide, andwater vapor prior to entering the reactor. The purification systemcomprised a pyrogallol solution, a sodium hydroxide solution, and dryingagents.

Ethylene was added to the autoclave containing the cyclohexane andcatalyst until a pressure of about 300 p.s.i.g. was reached. Theautoclave and contents were at a temperature of approximately 85 F. atthe time the ethylene was charged. The reactor and contents were heatedup gradually after the addition of the ethylene and at the end of about45 minutes the temperature had increased to 160 F. and the pressure wasabout 290 p.s.i.g. It is believed that the initiation of thepolymerization occurred at some point during this 45-minute period andbefore the temperature reached 160 F. At the end of the above-mentioned45-minute period the heat to the reactor was reduced and polymerizationallowed to continue for an additional 25 minutes. At the end of thisperiod, the temperature had increased to 187 F. At this point theheating of the reactor and contents was discontinued and an attempt wasmade to add additional ethylene to the reactor. It appeared that theline through which the ethylene entered the reactor may have beenpartially plugged and for that reason the gauge pressure may not havebeen an accurate indication of the actual pressure in the reactionvessel. This was indicated by the fact that the pressure indicated bythe gauge increased more rapidly than would normally be expected whenthe valve in the ethylene line was opened. However, since some ethylenewas being admitted to the reactor the polymerization was continued foran additional period of 1 hour and 40 minutes. During this period thereactor was repressured with ethylene at two different times as wasnecessary to maintain the pressure above approximately 275 p.s.i.g. Atthe end of the reaction period the temperature was about 160 F. and thepressure was about 250 p.s.i.g. At this point unreacted ethylene wasbled from the reactor and the reactor was cooled to room temperaturewith water. When the reactor was opened it was found that a portion ofthe polymer was present as a coating on the thermowell and a portion waspresent as cakes of solid material. Portions of the polymer were whitewhile other portions were tan in color. The solvent appeared to bedissolved in or absorbed by the solid polymer. The polymer wascomminuted in a Waring Blendor in the presence of methyl alcohol. Thefinely divided solid material was separated from the liquid and dried ina vacuum oven at about 172 F. and a pressure of less than mm. of mercuryabsolute. About 75 grams of a white powdered polymer of ethylene wasobtained.

The properties of a compression molded sample of this ethylene polymerare presented below in the table.

Flexibility Low The polymers and copolymers produced in accordance withthis invention have utility in applications where solid plastics areused. They can be molded to form articles of any desired shape, such asbottles and other containers Also, they can be formed into pipe by Aswill be evident to those skilled in the art many 'variations andmodifications can be practiced which fall within the scope of thedisclosure of this invention. The 'invention resides in an improvedpolymerization process for olefins as described herein comprising theuse of a novel catalyst composition and in the polymer so produced, saidcatalyst composition comprising at least one complex metal halide of theformula M MX where the symbols of the formula are as definedhereinabove, and at least one member selected from the group consistingof (a) a compound of a metal selected from the group consisting ofaluminum, gallium, indium, thallium, sodium, potassium, lithium,rubidium, cesium, beryllium, magnesium, zinc, cadmium and mercury havingthe valence linkages thereof individually bound to members selected fromthe group consisting of hydrogen, saturated acyclic hydrocarbonradicals, saturated cyclic hydrocarbon radicals, and aromatichydrocarbon radicals and alkali metal hydride, alkali metal alkyl andalkali metal aryl complexes of said compound of a metal; (b) anorgano-metal halide corresponding to the formula R MX wherein R is atleast one member selected from the group consisting of saturated acyclichydrocarbon radicals, saturated cyclic hydrocarbon radicals, andaromatic hydrocarbon radicals, M is a metal selected from the groupconsisting of aluminum, gallium, indium, thallium and beryllium, X is ahalogen, n and y are integers, the sum of n and y being equal to thevalence of said metal; (0) a mixture of an organic halide, and at leasti one free metal selected from the group consisting of sodium,potassium, lithium, rubidium, cesium, beryllium, magnesium, zinc,cadmium, mercury, aluminum, gallium, indium and thallium; and (d) ametal selected from the group consisting of sodium, potassium, lithium,rubidium, cesium, beryllium, magnesium, zinc, cadmium, mercury,aluminum, gallium, indium and thallium.

We claim:

1. A method for polymerizing a polymerizable hydrocarbon which comprisescontacting said hydrocarbon with a catalyst comprising a complex metalfluoride of the formula M M'F wherein M is an alkali metal and M is ametal selected from the group consisting of titanium and zirconium, anda member selected from the group consisting of (a) a trialkylaluminum,(b) an organometal halide corresponding to the formula R AlX wherein Ris an alkyl radical, X is a halogen, and n and y are integers, the sumof n and y being equal to the valence of aluminum, and (c) a mixture ofan alkyl halide and magnesium.

' 2. A method in accordance with claim 1 wherein said polymerizablehydrocarbon is an aliphatic l-olefin having up to and including 8 carbonatoms per molecule.

3. A method for polymerizing ethylene which comprises contacting saidethylene with a catalyst consisting essentially of a mixture ofpotassium fluotitanate and an approximately equimolar mixture ofethylaluminum dichloride and diethylaluminum chloride.

4. A method for polymerizing ethylene which comprises contacting saidethylene with a catalyst consisting essentially of a mixture ofpotassium fluotitanate and triethylaluminum.

5. A method for polymerizing ethylene which comprises contacting saidethylene with a catalyst consisting essentially of a mixture ofpotassium fluotitanate and lithium aluminum hydride.

6. A method for polymerizing ethylene which comprises contacting saidethylene with a catalyst consisting essentially of a mixture ofpotassium fluotitanate, ethylbromide and elemental magnesium.

7. A method for polymerizing ethylene which comprises contacting saidethylene with a catalyst consisting essentially of a mixture ofpotassium fluozirconate and an approximately equimolar mixture ofethylaluminum dichloride and diethylaluminum chloride.

8. A method for producing a solid polymer of an aliphatic l-olefinhaving up to and including 8 carbon atoms per molecule which comprisescontacting said olefin with a catalyst comprising a complex metalfluoride having the formula M M'F wherein M is an alkali metal and M isa metal selected from the group consisting of titanium and zirconium,and a member selected from the group consisting of (a) atrialkylaluminum, (b) an organometal halide corresponding to the formulaR AlX wherein R is an alkyl radical, X is a halogen, and n and y areintegers, the sum of n and y being equal to the valence of aluminum, and(c) a mixture of an alkyl halide and magnesium, at a temperature in therange from zero to 500 F., in the presence 'of a hydrocarbon diluent,inert and liquid under conditions of 10 the method, at a pressuresuificient to maintain said diluent in liquid phase, and recovering thesolid polymer so produced.

9. A method in accordance with claim 8 wherein the ratio of the amountof said complex metal halide and said members (a), (b), (c) and (d) insaid catalyst is in the following range: from 0.05 to 50 mols of saidmember (a) per mol of said complex metal halide; from 0.05 to 50 mols ofsaid member (b) per mol of said complex metal halide; from 0.02 to 50mols of said organic halide and from 0.02 to 50 mols of said free metalin said member (c) per mole of said complex metal halide; and from 0.02to 50 mols of said free metal defined in said member (d) per mol of saidcomplex metal halide.

10. A method in accordance with claim 8 wherein the ratio of the amountof said complex metal halide and said members (a), (b), (c) and (d) insaid catalyst is in the following range: from 0.1 to 5 mols of saidmember (a) per mol of said complex metal halide; from 0.1 to 5 mols ofsaid member (b) per mol of said complex metal halide; from 0.1 to 5 molsof said organic halide and from 0.1 to 5 mols of said free metal in saidmember (0) per mol of said complex metal halide; and from 0.1 to 5 molsof said free metal defined in said member (d) per mol of said complexmetal halide.

11. A method for polymerizing ethylene which comprises, contactingethylene with a catalyst consisting essentially of a mixture of from 0.1to 5 mols of an approximately equimolar mixture of diethylaluminumchloride and ethylaluminum dichloride per one mol of potassiumfluotitanate, in the presence of a hydrocarbon diluent, inert and liquidunder conditions of the method at a temperature in'the range from 100 to350 F. and a pressure in the range from 100 to 1000 p.s.i.g.

12. A catalyst composition comprising a complex metal fluoride havingthe formula M M'F wherein M is an alkali metal and M is a metal selectedfrom the group consisting of titanium and zirconium, and a memberselected from the group consisting of (a) a trialkylaluminum, (b) anorganometal halide corresponding to the formula R,,AlX,,, wherein R isan alkyl radical, X is a halogen, and n and y are integers, the sum of nand being equal to the valence of aluminum, and (c) a mixture of analkyl halide and magnesium.

13. A catalyst composition consisting essentially of a mixture ofpotassium fluotitanate, diethylaluminum chloride and ethylaluminumdichloride.

14. A catalyst composition consisting essentially of a mixture ofpotassium fluotitanate and triethylaluminum.

15. A catalyst composition consisting essentially of a mixture ofpotassium fluotitanate and lithium aluminum hydride.

16. A catalyst composition consisting essentially of a mixture ofpotassium fluotitanate, ethyl bromide and elemental magnesium.

17. A catalyst composition consisting essentially of a mixture ofpotassium fiuozirconate, diethylaluminum chloride and ethylaluminumdichloride.

References Cited in the file of this patent UNITED STATES PATENTS

1. A METHOD FOR POLYMERIZING A POLYMERIZABLE HYDROCARBON WHICH COMPRISESCONTACTING SAID HYDROCARBON WITH A CATALYST COMPRISING A COMPLEX METALFLUORIDE OF THE FORMULA M2M''F6 WHEREIN M IS AN ALKALI METAL AND M'' ISA METAL SELECTED FROM THE GROUP CONSISTING OF TITANIUM AND ZIRCONIUM,AND A MEMBER SELECTED FROM THE GROUP CONSISTING OF (A) ATRIALKYLALUMINUM, (B) AN ORGANOMETAL HALIDE CORRESPONDING TO THE FORMULARNAIXY, WHEREIN R IS AN ALKYL RADICAL, X IS A HALOGEN, AND N AND Y AREINTEGERS, THE SUM OF N AND Y BEING EQUAL TO THE VALENCE OF ALUMINUM, AND(C) A MIXTURE OF AN ALKYL HALIDE AND MAGNESIUM.